Many industrial processes produce olefins that are mixtures of functionalized internal olefins and functionalized alpha olefins. Olefins are frequently used in the manufacture of polymers, as drilling mud additives or as intermediates for the production of oil additives and detergents. Functionalized olefins, and in particular functionalized alpha olefins, may be used in applications such as polymers and chemical intermediates.
Depending upon the particular application, it would be desirable to manufacture a functionalized alpha olefin composition having the greatest purity possible. While pure species of functionalized alpha and internal olefins with a narrow carbon number range can be manufactured or produced in small quantities at a great cost, we have found that it would be particularly desirable to economically provide large quantities of separated and purified functionalized alpha and functionalized internal olefins from commercial raw feedstocks containing a mixture of functionalized internal olefins and functionalized alpha olefins. Examples include feeds containing the synthetic reaction products of syn-gas, such as those found in Fisher-Tropsch streams; by the oxidation of unsaturated and saturated hydrocarbons which often form unsaturated by-products; and the dehydrogenation of oxygenated hydrocarbons.
Separating and isolating functionalized alpha olefins from functionalized internal olefins is no easy task, especially when these species have similar or identical molecular weights or carbon numbers or when the only difference in the species one desires to separate is the position of the double bond. Conventional distillation methods are frequently inadequate to separate species of this type, which have such closely related boiling points. The separation problem is further aggravated in that the functionalized alpha olefin species not only needs to be separated from functionalized internal olefins, but also from those species containing differing functional groups and the saturated hydrocarbons.
U.S. Pat. No. 4,946,560 described a process for the separation of internal olefins from alpha olefins by contacting a feedstock with anthracene to form an olefin adduct, separating the adduct from the feedstock, dissociating the olefin adduct through heat to produce anthracene and an olefin composition enriched in alpha olefin, and separating out the anthracene from the alpha olefin. This reference does not suggest the desirability or the capability of anthracene to conduct a separation operation between functionalized alpha olefins and functionalized internal olefins.